A New Kind of Resonance

How modern technique and innovative yeast selection reshaped a classic beer style

People often ask if there is a philosophy or a common thread that connects the beers we brew at Fort Point. Many breweries will grab onto a handful of familiar aesthetics or styles as a compass — say, the cozy wooden pub with cask-conditioned English ales, or the esoteric barrel-aged sour factory. There are two words that I always come to when asked what we’re all about — balance and nuance. I’ll dive deeper into the how and why of those two words another time, but when it comes to describing the essence of the saison style, I think they’re both relevant.

Originally the name for a broad group of pale ales brewed to quench the thirst of farmworkers in the summer, the saison has evolved into something much more complex: spicy, fruity, and highly carbonated, saisons display a wide range of character — the result of generations of yeast evolution. The saison’s humble history and its potential to be incredibly expressive drew me to this style in the first place; saisons and farmhouse ales were really formative as I was first getting into beer. And that’s part of the story of how Resonance, our fresh take on the classic saison style, was born.

Prior to brewing Resonance, the majority of our experimental beers were hoppy pale ales and IPAs. Those beers are fun to brew, but they can start to feel monotonous, especially in the current hop craze. All told, brewing a saison as our next seasonal beer felt like a natural decision. But where to start? From the craziness of Fantôme to the precision of Brasserie de la Senne, farmhouse and saison beers cover a lot of ground. What kind of saison could Fort Point and only Fort Point make?

To answer that question, we held “The Grand Saison Tasting of 2016.” We gathered over 20 saison and farmhouse beers that ran the entire spectrum — peppery, elegant classics like Saison Dupont and Allagash Saison; funky barrel-fermented beers from Jolly Pumpkin; hop-driven modern takes from Off Color. After a long tasting and conversation we decided on two traits that we felt best complemented the rest of the Fort Point lineup: a dry foundation with slight tartness, and a mellow but fruity aroma, driven both by unique yeast character and restrained hop additions.

In May 2016, we released Resonance, our first saison, as part of a specialty series that included Manzanita, our smoked altbier and Moon Phase, a bourbon barrel-aged, Belgian-style quadrupel. At the time a 22-ounce bottle felt like a seemingly perfect package to signal the elegance and sophistication of the release. Afterall, classic saisons like Dupont and Fantôme are easily recognizable by their tall, green cork-topped bottles.

Our new Resonance can, alongside the first release in a 22oz. bottle

And yet, as we’ve grown as a brewery, we’ve fallen in love with the 12-ounce can. It’s a better quality package, and provides a great canvas for design. So for the 2018 release of Resonance, we’ve designed a can that we feel is just as refined as the bottle, but presents the beer in a smaller, more sessionable package. This year’s release has also allowed us to mine our experiences from the past year, and make technical improvements to what is already our most technically-challenging beer to brew. Below, I’ll get into some of the science behind these mysterious yeast strains and highlight a few techniques that we use to make this beautiful beer. If it’s a bit too technical or dense, go on and skip ahead, or (as always) reach out via email (mike@fortpointbeer.com) or Twitter and ask questions!


Resonance is a yeast-driven beer — the focus of many other beers is usually the flavors of the malt and hops, whereas the predominant flavors in Resonance are formed by the yeast during fermentation. The main variable that we are manipulating is the selection of specific yeast and bacteria. Yeast selection and fermentation dynamics play an important role in creating the peppery, spicy, and citrusy flavors for which saisons are known.

The compounds responsible for these flavors are called esters and phenols. Esters are created through reactions between alcohols and organic acids during fermentation. Different yeast strains are more prone to ester creation, but other factors such as temperature, wort composition, even the shape of the fermentor can either promote or suppress ester formation. Esters are typically associated with fruity aromas that range from apple to banana to pear. Phenols naturally exist in hops and malt but can also be derived through yeast metabolism. These compounds are associated with smoke, clove, or medicinal flavors. Most phenols are undesirable in beer, but a few styles rely on them (the clove-like flavor in Bavarian hefeweizen is from a phenol called 4-vinyl guaiacol).

We knew yeast would play a large role in developing the fruity aroma of this beer, but we also needed it to set up the foundation and texture. This posed a unique challenge that we met with a pragmatic solution — use two yeast strains! Most sour beers are made with multiple yeast and bacteria strains co-fermenting together. Over time, the conditions in the beer change, giving each organism its time to shine and contribute to the final product. Mixed fermentations are a useful technique to give a beer more depth of flavor, however it’s an inexact science. Different yeast strains reproduce at different rates, so the 50/50 blend that you start with could shift into a 70/30 blend after the yeast is harvested and reused again, leaving you with a different flavor profile than your original beer. We wanted to separate the two strains so that we could harvest them individually and maintain the right ratio for each subsequent batch of beer.

Resonance, then, is a combination of two separate fermentations working in harmony. The same batch of wort is split into two tanks, then each tank is pitched with a different strain. The first is a French saison yeast purportedly isolated from the Thiriez brewery in Esquelbecq, France. This yeast is a moderate ester and phenol producer and leaves the beer with a silky mouthfeel while establishing a structured foundation. We ferment this strain at a lower temperature to suppress the production of the esters and phenols, since we want the majority of the fruity flavors to come from the second yeast strain (as well as a small addition of hops).

That second strain is called Saccharomyces Trois. It is believed to originate from a brewery in Belgium and was originally thought to be a member of the Brettanomyces genus. Recent advances in genetic sequencing determined that despite its Brettanomyces characteristics (lack of flocculation, pellicle formation, and flavor compound production not typical of any brewing species of Saccharomyces), it was actually best classified as a wild Saccharomyces strain¹. This strain is the big flavor driver in Resonance, exploding with aromas of mango and pineapple.

None of these great flavors can happen if the yeast don’t have anything to eat, so we add a simple grist of Weyermann Bohemian Pilsner, Weyermann Pale Wheat, Weyermann Carafoam, and Weyermann Acidulated malt to create a soft, mild pale-colored wort. The wheat and Carafoam help give the beer body, while the Acidulated malt helps us regulate pH in the mash tun, as well as add a little zip.

Now, “mouthfeel” is a term you might hear used in beer descriptions. While it’s not the most appealing-sounding word, the texture of the beer has a lot to do with how enjoyable it is — and this is absolutely true for Resonance, which we designed to be incredibly refreshing while still having substance to it. Our two yeast strains contribute a lot to the texture, but there’s one extra step we use to brighten the beer up even more: the sour mash!

Kettle souring is a technique used to rapidly sour wort by providing lactic acid-producing bacteria with the optimal conditions for growth — no oxygen and a temperature around 100°F. Bacteria can be introduced to the wort in a number of ways. Since these bacteria naturally exist on grain, you can steep grain in the wort or allow the wort to sit on the spent grain until the bacteria begin to take off. Brewers will also use yogurt or probiotics to introduce the desired bacteria to the wort. After a lot of research and experimentation, we settled on using a dried bacteria culture to inoculate the wort. This gives us more control since we are able to know exactly what strain we are using and how much we are pitching. Our pitch is a monoculture strain of Lactobacillus plantarum that produces a clean tartness accented by light citrus flavors.

The strategy behind our sour wort technique is to create a pleasant tartness and acidity that lingers in the background of the beer. We prepare a simple wort a few days before Resonance brew day and inoculate it with our bacteria culture. It then rests for 24 to 48 hours until hitting a target pH and acidity. At that point, the wort is boiled to halt the growth of the bacteria and sterilize it for fermentation with the two yeast strains mentioned above. This sour wort is blended into the fresh wort, creating tartness without the risk of infection further down the road.

A lot of time and technique goes into creating Resonance, and that was part of the inspiration for the name. Similar to an orchestra, where several small sounds weave together to combine into something powerful and layered, Resonance is the product of multiple yeasts and bacterias working their individual magic, then combining into something greater than the sum of their parts. The name is also a reference to the deep roots of the saison style and its influence on our brewing philosophy. Things that are timeless — art, music, beer — stay with you and take on new meanings. All the beers we’ve had along the way have resonated with us, and they shape the beer that we’ll be making tomorrow. Resonance is in honor of those beers, and a celebration of how much we love brewing … even if we make it complicated. Cheers!

¹ https://www.whitelabs.com/sites/default/files/644_Explanation.pdf


Mike Schnebeck is the head brewer at Fort Point Beer Company.

Curious about the origin of our other beers? Read about how KSA came to be in our blog post here, or the story of another of our seasonal beers, Manzanita, here.